The 38-year-old singer and his wife Chrissy Teigen conceived their nine-month-old daughter Luna through in-vitro fertilisation, which is where eggs are collected and fertilised by sperm in a lab, then implanted back into the woman's uterus.

The All of Me hitmaker has urged other couples who are having fertility issues to try IVF, after it worked so well for him and Chrissy. "There are some who look down on people that have fertility issues and need to use IVF. We have had fertility issues for years and had to use IVF," he told Newsweek Europe.